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Capacitor Banks, Cells, & Fuses - Inspection & Maintenance Procedures
(46 pgs.)
TOM ERSIN
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Capacitor Banks, Cells, & Fuses - Inspection & Maintenance Procedures
(46 pgs.)
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or clarity improvements from the field view.
CONTENTS
(press-and-hold “Ctrl” while clicking link)
DANGER
PRIOR TO ENERGIZING A PREVIOUSLY-FAILED CAPACITOR BANK, THE “CAPACITOR
BANK TROUBLESHOOTING SEQUENCE GUIDE” (Section V) MUST BE COMPLETED!
-) SAFETY
-) SCOPE & RESPONSIBILITY
-) QUICK REFERENCE (Equipment/Special Tools, Materials, Documentation)
I)
CAPACITOR CELLS – FAILURES & BLOWN FUSES
II) CAPACITOR-CELL FUSES – MAINTENANCE
-) SCOPE
A) CAPACITOR CELL INSPECTIONS
1) CAPACITOR BANK PROBLEMS
2) CAPACITOR-CELL FUSE
3) VISUAL INSPECTIONS
B) CAPACITOR CELL TESTING
C) FUSE REPLACEMENT
III) CAPACITOR-CELL FUSES – PRODUCT INFO
1) FUSE SPRINGS – GE: OLD (DISCONTINUED) & NEW
2) PRODUCT INFO
A) Capacitor Bank – 13.2-kV; 6-mVAR Max.; 200-kVAR Capacitor Cells; CurrentLimiting Fuses
B) Capacitor Bank – 24-kV; 18-mVAR Max.; 100-kVAR Capacitor Cells; Expulsion
Fuses
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Capacitor Banks, Cells, & Fuses - Inspection & Maintenance Procedures
(46 pgs.)
C) Capacitor Bank – 24-kV; 18-mVAR Max.; 200-kVAR Capacitor Cells; Expulsion
Fuses
D) Capacitor Bank – 24-kV; 36-mVAR Max.; 200-kVAR Capacitor Cells; CurrentLimiting Fuses
E) Capacitor Bank – 40-kV; 18-mVAR Max.; 100-kVAR Capacitor Cells; Expulsion
Fuses
F) Capacitor Bank – 40-kV; 18-mVAR Max.; 200-kVAR Capacitor Cells; Expulsion
Fuses
G) Capacitor Bank – 40-kV; 36-mVAR Max.; 200-kVAR Capacitor Cells; CurrentLimiting Fuses
H) Capacitor Bank – 40-kVAR; 500-kVAR; 550-kVAR Capacitor Cells; Fuseless
IV) BANKGUARD CAPACITOR RELAYING – 59-N (aka 59-N BCR)
-) SCOPE
1) OPERATIONS
2) ALARMS
3) PROTECTION
V) CAPACITOR BANK TROUBLESHOOTING SEQUENCE GUIDE
1) FUSED 24-kV & 40-kV
2) FUSELESS 24-kV & 40-kV
VI) CAPACITOR BANK BALANCING
-) SCOPE
1) BALANCING
A) 13.2-kV BANKS
B) 24-kV & 40-kV BANKS
1) WYE-UNGROUNDED
2) WYE-GROUNDED
C) GENERAL
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Capacitor Banks, Cells, & Fuses - Inspection & Maintenance Procedures
(46 pgs.)
VII) CAPACITOR (aka “SHUNT CAPACITOR”) THEORY & OPERATION
1) PURPOSE
2) CONSTRUCTION & CONNECTIONS
A) CAPACITOR CELLS
B) CAPACITOR BANK INSTALLATIONS
C) CAPACITOR DISCHARGE
3) OPERATING INFORMATION
FIGURES
Capacitance Value Ranges for Power-Shunt Caps
Table 01
Capacitor Bank Group & Fuses
Figure 08
Capacitor Bank Installations
Figure 09
Current Flow
Figure 10
Fluke Multi-Meter
Figure 11
Fluke Multi-Meter
Figure 12
Fuse Element Components
Figure 13
Fuse Element – Horizontal Bushing Assembly
Figure 14
Fuse Element – Vertical Bushing Assembly
Figure 15
Fuses, Construction, & Connections
Figure 07
Lockout Relay (LOR)
Figure 06
Springs – Old and New Style
Figure 16
Strings & Measurement Points
Figure 17
Voltage-Sensing Potential Device
Figure 05
Wye-Grounded Capacitor Bank – Left-Side Rack In-Series with Right-Side Rack
Figure 04
Wye-Grounded Capacitor Bank – Upper Rack In-Series with Lower Rack
Figure 03
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Capacitor Banks, Cells, & Fuses - Inspection & Maintenance Procedures
(46 pgs.)
Wye-Ungrounded Capacitor Bank – Left-Side Rack In-Series with Right-Side Rack
Figure 02
Wye-Ungrounded Capacitor Bank – Upper Rack In-Series with Lower Rack
Figure 01
-) SAFETY
[top]
This is a safe-use guide for the described equipment. Only qualified personnel should
proceed. Keep these instructions available to all Substation personnel. Read these
instructions carefully before proceeding. Otherwise, serious injury or equipment
damage could occur. FOLLOW ALL DTE & MIOSHA SAFETY REGULATIONS.
FRC/PPE
— WEAR ALL NECESSARY FLAME RESISTANT CLOTHING (FRC) & PERSONAL
PROTECTIVE EQUIPMENT (PPE) WHILE PERFORMING ANY PROCEDURES IN
THIS ARTICLE.
— ALL JOBS ON POWER EQUIPMENT REQUIRE MINIMUM OF CATEGORY 2 FRC.
— EQUIPMENT ENERGIZED TO ≥ 600-V MIGHT REQUIRE HIGHER FRC CATEGORY.
REFER TO DTE ENERGY ELECTRICAL SAFETY STANDARDS.
— THIS WORK REQUIRES SAFETY GLASSES WITH SIDE SHIELDS OR GOGGLES.
-) SCOPE & RESPONSIBILITY
[top]
A) This article provides instructions unique to this class of circuit breaker.
B) Qualified maintenance personnel must perform these procedures (adjustment, testing,
and inspection) as scheduled. Additionally, they will perform any other necessary
maintenance – with prior approval, if required, from the equipment engineer.
C) Circuit breaker testing results must fall within all established testing values. Any
deviations must be resolved with equipment engineer and/or manufacturer.
DANGER
1) BEFORE TESTING OR WORKING ON CIRCUIT BREAKER OR MECHANISM,
EQUIPMENT MUST BE PROTECTED AGAINST ALL SOURCES OF POTENTIAL &
STORED ENERGY BY ENSURING THE FOLLOWING:
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Capacitor Banks, Cells, & Fuses - Inspection & Maintenance Procedures
(46 pgs.)
— ALL DISCONNECTS ARE OPEN, OR OUTSIDE PROTECTION IS PROVIDED IF
NEEDED
— BREAKER IS COMPLETELY DE-ENERGIZED
[IF APPLICABLE]
ON SPRING-TYPE MECHANISMS, SPRINGS MUST BE DISCHARGED, &
CIRCUIT BREAKER MUST BE OPEN & RACKED OUT
[IF APPLICABLE]
ON PNEUMATIC & HYDRAULIC MECHANISMS, PRESSURE SUPPLY
VALVE IS CLOSED & PRESSURE DRAIN VALVE IS OPEN
— REQUIRED BARRIERS & TAGS ARE IN PLACE
2) IF A FAULTY CONDITION ARISES DURING ANY INSPECTIONS / PROCEDURES, THE
NECESSARY REPAIRS OR ADJUSTMENTS MUST BE PERFORMED BEFORE
PROCEEDING.
3) REVIEW ALL MANUFACTURER’S WARNINGS AND CAUTIONS.
4) PRIOR TO APPLYING TEST POTENTIAL, ENSURE ALL PERSONNEL ARE CLEAR
OF EQUIPMENT BEING TESTED.
5) DO NOT HI-POT OR INSULATION-RESISTANCE TEST (MEGGER) ANY SOLID STATE
DEVICES.
6) PRIOR TO ANY FUNCTIONAL TESTS, VERIFY THAT OPERATION OF AUXILIARY
SWITCHES — CONNECTED IN CONTROL CIRCUITS OF OTHER SYSTEMS — WILL
NOT ENDANGER PERSONNEL AND EQUIPMENT OUTSIDE BREAKER OR
EQUIPMENT BEING TESTED.
DANGER
PRIOR TO ENERGIZING A PREVIOUSLY-FAILED CAPACITOR BANK, THE “CAPACITOR
BANK TROUBLESHOOTING SEQUENCE GUIDE” (Section V) MUST BE COMPLETED!
-) QUICK REFERENCE (Equipment/Special Tools, Documentation)
[top]
•
Equipment/Special Tools
1) conductivity tester
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Capacitor Banks, Cells, & Fuses - Inspection & Maintenance Procedures
(46 pgs.)
2) insulation resistance tester (Megger) (500-2500-V)
3) multi-meter
4) scale (6-inch)
5) step-transformer
6) test leads – various
7) timing device
8) variac rectifier set
I)
CAPACITOR CELLS – FAILURES & BLOWN FUSES
[top]
WARNING
DIELECTRIC LIQUIDS & CAPACITOR CELLS:
— PERSONNEL MUST WEAR OIL-IMPERVIOUS GLOVES (STOCK NO. 981-0014) &
COVER-ALL GOGGLES (STOCK NO. 981-0190) WHEN WORKING WITH LEAKING
CAPACITOR CELLS, DIELECTRIC-SPLASH CLEANUP, OR ANY OTHER
POSSIBLE DIELECTRIC-LIQUID CONTACT.
— CHECK GLOVE INTEGRITY BEFORE EVERY JOB.
— AFTER COMPLETING JOB, WASH HANDS & FACE WITH WARM WATER & SOAP.
— ANYTHING THAT COMES IN CONTACT WITH DIELECTRIC SPLASH MUST BE
SEALED IN A CLAMP-TOP DRUM CONTAINER & SENT TO SALVAGE-WSC.
- THIS INCLUDES RAGS, CLOTHES, STONES, DIRT, & LEAKING,
RUPTURED, OR PUNCTURED CAPACITOR CELLS.
- DEFECTIVE CAPACITOR CELLS SENT TO SALVAGE-WSC MUST BE
PROMPTLY FOLLOWED BY A MEMO TO THE “INSULATION
COORDINATOR” STATING LOCATION, CAPACITOR CELL MAKE, CATALOG
NO., SERIAL NO., kVAR RATING, VOLTAGE LEVEL, REASON FOR
SCRAPPING, & REMOVAL DATE.
[top]
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Capacitor Banks, Cells, & Fuses - Inspection & Maintenance Procedures
(46 pgs.)
A) See Section II: CAPACITOR-CELL FUSES-MAINTENANCE to if cell, fuse, or both need
replacement.
B) Refer to “Maintenance Letter 346” for proper reporting of failed capacitor cells.
C) If replacement capacitor cells or fuses are unavailable, capacitor banks MUST be
balanced to avoid overvoltage on remaining banks. See Section VI: CAPACITOR BANK
BALANCING.
II)
CAPACITOR-CELL FUSES – MAINTENANCE
(back)
[top]
-) SCOPE
A) Defective or Blown Fuse Element
Substation Operator will change a defective or blown fuse element in a capacitor cell, as
soon as conditions permit, to restore service.
B) Defective Capacitor Cell
Substation Operator will submit an OFW to Substation Maintenance to replace a
defective capacitor cell and its fuse element.
1) CAPACITOR CELL INSPECTIONS
[top]
A) Capacitor Bank Problems
•
Capacitor-bank problems usually occur in one of its individual capacitor cells.
B) Capacitor-Cell Fuse
[top]
•
Each capacitor cell within a capacitor bank is typically fused (fuse-protected). If a
capacitor-cell disturbance occurs, the fuse should blow, which disconnects capacitor
cell from capacitor bank.
[NOTE]
Some capacitor-bank installations are non-fused.
C) Visual Inspections
[top]
Other common problems are caused by corroded or fatigued fuse elements. Therefore,
Substation Operator will visually inspect all components of a capacitor bank that is shut
down for maintenance. This includes the following:
1) Fuses and Fuse Connections
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Capacitor Banks, Cells, & Fuses - Inspection & Maintenance Procedures
•
(46 pgs.)
Replace fuse if any of the following are found:
i)
loose, frayed, corroded, or otherwise deteriorated components
ii)
melted or broken-open links
iii)
deteriorated horn fiber (from moisture entering open end of fuse tube)
iv)
swollen horn-fiber insert (impedes ejection of tail from fuse tube)
v)
horn fiber used as insect nest
vi)
swollen fuse tubes (in some McGraw-Edison cells) (compromises integrity
of outside Bakelite tube)
2) Capacitor Cells
a) Remove any wildlife nesting (e.g., bird or wasp nests) during shutdown.
b) Submit an OFW for Substation Maintenance to replace a capacitor cell if any of
the following are found:
i)
broken, cracked, or chipped cell bushings
ii)
leaking, bulging, ruptured, punctured, charred, or otherwise damaged cells
3) Electrical Connections
•
Submit an OFW for Substation Maintenance to inspect/repair connections if any
of the following are found:
o
loose or corroded connections
4) Capacitor Rack and Support Insulators
•
Submit an OFW for Substation Maintenance to make repairs if any of the
following are found:
o
tracking, arcing, cracked, chipped, or broken rack components or insulators
2) CAPACITOR CELL TESTING (see Figures 11 & 12)
[top]
A) After capacitor bank is shut down and properly protected (see Article 405), Substation
Operator will test capacitor cell for proper capacitance before replacing its fuse element.
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Capacitor Banks, Cells, & Fuses - Inspection & Maintenance Procedures
(46 pgs.)
B) This testing is done with a hand-held, battery-operated Fluke Multi-Meter – set to
“Capacitance Tester” – as follows:
1) Insert test leads into Fluke Multi-Meter. (see Figure 11).
•
RED TEST LEAD goes into the “Volts, Ohms, Diode Test” receptacle.
•
BLACK LEAD goes into the “Common Terminal.”
2) Turn rotary switch to capacitance setting: “Ω /
“
3) Press and hold down YELLOW KEY for two (2) full seconds. “µF” will appear on
LCD screen.
4) Connect multi-meter lead probes across terminals of capacitor cell with blown fuse.
LCD screen will display “OL” momentarily, then, will automatically switch back to
“µF.”
5) Record capacitance reading, and compare it with the acceptable capacitance value,
listed in TABLE 01: CAPACITANCE VALUE RANGES FOR POWER SHUNT
CAPACITORS.
6) If capacitance value is WITHIN acceptable range (from Table 01), install new fuse in
capacitor cell.
7) If capacitance value is OUTSIDE of acceptable range, do NOT install new fuse in
capacitor cell. Submit OFW to Substation Maintenance for defective capacitor cell
replacement.
3) FUSE REPLACEMENT (see Figures 13, 14, & 15)
[top]
A) If performing a blanket replacement of all fuse tubes, old tubes will be sent to, and
inspected at, Maintenance Headquarters to salvage any that are re-usable.
•
•
Salvageable fuse tubes are characterized by the following:
o
fuse link must freely slip out of tube when held vertically with the ferrule down
o
fuse-tube’s insides must be perfectly smooth
Fuse LEADERS (LINKS) are NOT salvageable – their tails were custom-cut for each
location and likely will not fit other locations
B) Wherever a capacitor cell has caused its fuse element to blow, replace BOTH
components.
C) When a capacitor cell blows its fuse – and the cell appears normal – Substation
Operator will test cell for defect.
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Capacitor Banks, Cells, & Fuses - Inspection & Maintenance Procedures
(46 pgs.)
NOTICE
SUBSTATION OPERATOR WILL SUBMIT AN OFW TO SUBSTATION MAINTENANCE FOR
DEFECTIVE CELL REPLACEMENT.
[top]
D) After determining that a capacitor cell is NOT defective, Substation Operator will replace
defective fuse unit as follows:
1) Perform required switching and protective procedures to shut down capacitor bank.
2) Unscrew fuse tube, and remove defective unit.
3) Check for fuse tube obstruction from mud daubers, dirt, moisture swelling, etc. Clear
any obstruction.
4) Ensure replacement fuse tube and leader (link) are proper size
(see Section III, 2, D).
5) Do NOT cut fuse tube to shorten it. They are sized according to capacitor-cell
voltage rating.
6) Feed new fuse leader (link) through fuse tube.
•
Check for, and reject, any leader (link) damaged by crimps, bends, or frayed
leader wire.
7) Ensure that fuse’s knurled bolt is tight and its washer is in place (see Figure 15).
8) Screw fuse tube back onto its rack.
9) Remove jamb nut from bushing terminal.
10) Remove fuse clamp.
11) Remove defective fuse leader (link), if it is still present.
12) Bend flipper spring up toward fuse-tube end so that it is ≤ one (1) inch from tube.
•
Visually inspect flipper-spring integrity (see Section III, 1 regarding discontinued
old-style GE flipper spring – with bracket – which must be replaced).
o
When a fuse blows, an improperly installed or poorly designed flipper spring
can cause “leader whipping” (a swinging faulted leader, which could contact –
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Capacitor Banks, Cells, & Fuses - Inspection & Maintenance Procedures
(46 pgs.)
or arc with – neighboring fuse leaders (links) or capacitor cells, possibly
causing a “domino” effect of multiple capacitor-cell failures and fires).
13) Feed fuse leader (link) through eye-end of fuse spring.
14) Wrap fuse leader (link) – clockwise – around terminal bushing.
•
Ensure that leader (link) is not binding with flipper.
15) Replace fuse clamp.
16) Replace jamb nut, and tighten it.
17) Cut off any excess fuse leader (link).
III)
CAPACITOR-CELL FUSES – PRODUCT INFO
[top]
1) FUSE SPRINGS – GE: OLD (DISCONTINUED) & NEW
(back)
A) OLD GE capacitor-cell fuse spring – identified by a bracket supporting the flipper
spring (see Figure 16)
•
Old GE capacitor-cell fuse springs must be replaced.
B) NEW GE capacitor-cell fuse spring (used since 1984) – has NO bracket supporting
the spring (see Figure 16)
2) PRODUCT INFO
[top]
A) Capacitor Bank – 13.2-kV; 6-mVAR Max.; 200-kVAR Capacitor Cells; CurrentLimiting Fuses
1) Capacitor Cells – 200-kVAR; 7.62-kV (2-bushings)
•
Edison Stock # 666-9174
•
Approved Manufacturers: GE (Cat. # 58L107WC70); Cooper Power Systems
(Cat. # CUM00011Y1 – includes capacitor cell and current-limiting fuse)
2) Current-Limiting Fuses
•
Edison Stock # 666-9106
•
Approved Manufacturer: Cooper Power Systems (8.3-kV; 40-A); Type NXC (Cat.
# FA5J40)
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Capacitor Banks, Cells, & Fuses - Inspection & Maintenance Procedures
(46 pgs.)
B) Capacitor Bank – 24-kV; 18-mVAR Max.; 100-kVAR Capacitor Cells; Expulsion
Fuses
[top]
1) Capacitor Cells – 100-kVAR; 6.9-kV
•
Edison Stock # 666-9016
•
Approved Manufacturers: GE (Cat. # 54L316WC70); Cooper Power Systems
(Cat. # CUM00011Y2 – includes capacitor cell and current-limiting fuse)
2) Fuse Tubes
•
Edison Stock # 666-9020
•
Approved Manufacturers: GE (Cat. # 115A1615G41); Cooper Power Systems
(Cat. # CCM149B1)
3) Fuse Flipper Springs
•
Edison Stock # 666-9019
•
Approved Manufacturer: GE (Cat. # 248A6954G1)
4) Fuse Links – 25-kV
•
Edison Stock # 703-0123
C) Capacitor Bank – 24-kV; 18-mVAR Max.; 200-kVAR Capacitor Cells; Expulsion
Fuses
[top]
1) Capacitor Cells – 200-kVAR; 6.9-kV
(back)
•
Edison Stock # 666-9040
•
Approved Manufacturers: Cooper Power Systems (Cat. # CUM00011Y3 –
includes capacitor cell and fuse link)
Recommendation
Try to stock only the above-listed brands, for the following reasons:
o
tight clearances between fuse and top of capacitor-cell bushing
o
all capacitor cell sizes vary between manufacturers
Failed 200-kVAR capacitor cells – while still under warranty – are returned to,
and replaced by, the manufacturer. When manufacturer replacements arrive,
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Capacitor Banks, Cells, & Fuses - Inspection & Maintenance Procedures
(46 pgs.)
send them back to the Maintenance Headquarters that originally handled the
failed cells. That Maintenance Department should then place these replacement
cells in same-make capacitor banks.
2) Fuse Tubes
•
Edison Stock # 666-9020
•
Approved Manufacturers: GE (Cat. # 115A1615G41); Cooper Power Systems
(Cat. # CCM149B1)
3) Fuse-Flipper Springs
a) Horizontal Mounting
•
Edison Stock # 666-9053
•
Approved Manufacturer: GE (Cat. # 248A6954G1)
b) Vertical Mounting
•
Edison Stock # 666-9019
•
Approved Manufacturer: GE (Cat. # 248A6954G1)
4) Fuse Links – 40-kV
•
Edison Stock # 703-0124
D) Capacitor Bank – 24-kV; 36-mVAR Max.; 200-kVAR Capacitor Cells; CurrentLimiting Fuses
(back)
[top]
1) Capacitor Cells – 200-kVAR; 6.9-kV
•
Edison Stock # 666-9995
•
Approved Manufacturers: Cooper Power Systems (Cat. # CUM00011Y4 –
includes capacitor cell and current-limiting fuse) (see Section III, 2, C, 1 for
replacement policy)
2) Current-Limiting Fuses
•
Edison Stock # 666-9106
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Capacitor Banks, Cells, & Fuses - Inspection & Maintenance Procedures
•
(46 pgs.)
Approved Manufacturer: Cooper Power Systems (8.3-kV; 40-A); Type NXC (Cat.
# FA5J40)
3) All capacitor banks rated at 24-kV; up to 36 mVAR – except McGraw-Edison
capacitor banks – may be equipped with either Westinghouse CLXP or COL fuses.
These cells have a current-limiting fuse and expulsion link, in-series. Whenever
these fuses are blown or damaged, replace entire unit with an NXC current-limiting
fuse.
E) Capacitor Bank – 40-kV; 18-mVAR Max.; 100-kVAR Capacitor Cells; Expulsion
Fuses
[top]
1) Capacitor Cells – 100-kVAR; 12-kV
•
Edison Stock # 666-9014
•
Approved Manufacturers: GE (Cat. # 54L301WC70); Cooper Power Systems
(Cat. # CUM00011Y6 – includes capacitor cell and fuse link)
2) Fuse Tubes
•
Edison Stock # 709-0096
•
Approved Manufacturers: GE (Cat. # 31F2807G1); Cooper Power Systems (Cat.
# FN3Y2C)
3) Fuse-Flipper Springs
•
Edison Stock # 666-9019
•
Approved Manufacturer: GE (Cat. # 248A6954G1)
4) Fuse Links – 15-kV
•
Edison Stock # 703-0127
F) Capacitor Bank – 40-kV; 18-mVAR Max.; 200-kVAR Capacitor Cells; Expulsion
Fuses
[top]
1) Capacitor Cells – 200-kVAR; 12-kV
•
Edison Stock # 666-9039
•
Approved Manufacturers: Cooper Power Systems (Cat. # CUM00011Y7 –
includes capacitor cell and fuse link) (see Section III, 2, C, 1 for replacement
policy)
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Capacitor Banks, Cells, & Fuses - Inspection & Maintenance Procedures
(46 pgs.)
2) Fuse Tubes
•
Edison Stock # 709-0096
•
Approved Manufacturers: GE (Cat. # 31F2807G1); Cooper Power Systems (Cat.
# FN3Y2C)
3) Fuse-Flipper Springs
•
•
Horizontal Mounting
o
Edison Stock # 666-9053
o
Approved Manufacturer: GE (Cat. # 248A6954G2)
Vertical Mounting
o
Edison Stock # 666-9019
o
Approved Manufacturer: GE (Cat. # 248A6954G1)
4) Fuse Links (25-kV)
•
Edison Stock # 703-0123
G) Capacitor Bank – 40-kV; 36-mVAR Max.; 200-kVAR Capacitor Cells; CurrentLimiting Fuses
[top]
1) Capacitor Cells – 200-kVAR; 12-kV
•
Edison Stock # 666-9996
•
Approved Manufacturers: Cooper Power Systems (Cat. # CUM00011Y8 –
includes capacitor cell and current-limiting fuse) (see Section III, 2, C, 1 for
replacement policy)
2) Current-Limiting Fuses
•
Edison Stock # 666-9122
•
Approved Manufacturer: Cooper Power Systems (15-kV; 25-A); Type NXC (Cat.
# FA6J25)
4) All 40-kV capacitor banks rated up to 36mVARS — except Cooper Power Systems
banks — may be equipped with either Westinghouse CLXP or COL fuses. Whenever
these fuses are blown or damaged, replace entire unit with an NXC current-limiting
fuse.
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(46 pgs.)
H) Capacitor Bank – 40-kV Fuseless
[top]
1) Capacitor Cells – 400-kVAR; 12-kV
•
Edison Stock # 666-9992
•
Approved Manufacturers: Cooper Power Systems (Cat. # CEP99205A1)
2) Capacitor Cells — 500-kVAR; 12-kV
•
Edison Stock # 666-9991
•
Approved Manufacturers: Cooper Power Systems (Cat. # CEP99169A1)
3) Capacitor Cells — 550-kVAR; 12-kV
•
Approved Manufacturers: Cooper Power Systems (Cat. # CEP06095A1)
IV) BANKGUARD CAPACITOR RELAYING – 59-N
(aka 59-N BCR)
[top]
-) SCOPE (see Figures 05 & 06)
A) 59-N bankguard capacitor relaying (59-N BCR) is designed to reduce voltage
disturbances on the DTE Energy sub-transmission system, with the goal of preventing
catastrophic equipment failure.
B) The most common 59-N bankguard capacitor relaying (59-N BCR) scheme consists of a
voltage-sensing potential device installed between the 40-kV capacitor-bank neutral
bus and the substation ground mat.
C) When the potential device (see Figures 05 & 06) senses a trouble-indicating neutral-bus
voltage, it energizes a lockout relay (LOR), which isolates the capacitor bank and locks
out the capacitor switcher.
1) OPERATIONS
[top]
This bankguard relaying scheme engages when neutral-bus voltage reaches a certain
value: the equivalent of four (4) capacitor cells failing on one (1) phase.
A) In most substations, when this value is detected, the 59-N BCR energizes its 1_ _94
LOR, which trips and locks out the capacitor switcher.
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Capacitor Banks, Cells, & Fuses - Inspection & Maintenance Procedures
•
(46 pgs.)
In these installations, a diode is installed within the 40-kV circuit breaker. This
prevents breaker from tripping if the problematic neutral-bus voltage value is caused
by a capacitor failure.
B) In substations where fault capacity exceeds 30-kA, the 1_ _94 LOR will do the
following:
1) Trip the 40-kV trunk or tie-line circuit breaker.
2) Lockout the capacitor switcher.
3) Allow trunk or tie-line circuit breaker to reclose.
C) Two other possible substation events could generate a voltage difference between
ground and capacitor neutral bus:
1) A fault could occur within substation ground mat, elevating the potential of that
ground.
•
This is rare, and sufficient relay protection would be cost-prohibitive.
The protection provided by such a scheme yields the same results as the 59-N
bankguard relaying scheme; every protected capacitor in the affected area would
be isolated.
2) Trouble could arise on equipment connected to capacitor bank, creating voltage
spikes that could rupture capacitor cells.
a) When capacitor-bank-connected equipment fails, the capacitors should
automatically drain through faulted equipment. But this is NOT guaranteed, and
subsequent reclosures can prompt capacitor-cell failures to cascade.
b) Therefore, whenever any capacitor-bank-connected equipment energizes its own
protective relay to trip the circuit breaker, it also energizes the 59-N BCR LOR to
isolate capacitor bank. The affected circuit breaker then completes its normal
reclosing cycle.
2) ALARMS
[top]
A) The 59-N BCR scheme and the 1_ _94 LOR are alarmed separately. Whenever the 59N BCR picks up and isolates the capacitor switcher, there should be TWO (2) alarms to
acknowledge.
1) A 59-N operation is indicated by the RED LAMP mounted to face of bankguard relay
panel. Reset it by pushing button also mounted on panel.
2) Alarm switch for 1_ _94 LOR is located on switchboard panel. Acknowledge by
engaging the toggle-switch.
19
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Capacitor Banks, Cells, & Fuses - Inspection & Maintenance Procedures
(46 pgs.)
B) If protective relays on trunk or tie-line initiate a capacitor-switcher lockout, a circuitbreaker alarm AND a 1_ _94 alarm will be generated. However, the trunk or tie-line
circuit breaker may remain closed upon capacitor-switcher’s reclosure. This would
cancel one of the alarms.
3) PROTECTION
[top]
Since the 59-N BCR system contains a potential device, a secondary switch is installed on
the device. This secondary switch is located within the capacitor-switcher control
compartment – OR – within a weatherproof box mounted (below) the potential device, inside
the capacitor fenced enclosure. This secondary switch is considered a protective
tagging point.
NOTICE
— THE RED INDICATING LAMPS LOCATED ON THE 59-N BCR PANEL ARE SELFCONTAINED UNITS.
— SUBSTATION OPERATOR WILL SUBMIT A “FIVE (5)-DAY URGENT OFW” IF THIS
LAMP NEEDS REPLACEMENT.
V)
CAPACITOR BANK TROUBLESHOOTING SEQUENCE
GUIDE
(back)
[top]
DANGER
PRIOR TO ENERGIZING A PREVIOUSLY-FAILED CAPACITOR BANK, THIS “CAPACITOR
BANK TROUBLESHOOTING SEQUENCE GUIDE” (Section V) MUST BE COMPLETED!
1) FUSED 24-kV & 40-kV
[top]
A) Inspect for, and note, capacitor-cell blown fuses and capacitor-cell bulges.
B) Inspect for, and note, YELLOW TARGETS and/or RED TARGETS on capacitor
switcher.
20
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Capacitor Banks, Cells, & Fuses - Inspection & Maintenance Procedures
(46 pgs.)
C) Then, follow this troubleshooting sequence:
1) If Step 1 issues (blown fuses, bulged cells) are found, follow Step 4: Capacitor Banks
Diagnosis Sequence (below).
2) If Step 2 issues (targets on switcher) are found, follow Step 5: Switcher Diagnosis
Sequence (below).
3) If Step 1 AND Step 2 issues are found, follow Step 4: Capacitor Banks Diagnosis
Sequence AND Step 5: Switcher Diagnosis Sequence, in-parallel (below).
D) Capacitor Banks Diagnosis Sequence
[top]
1) Verify that “Red Tag Protection” has been applied.
2) Do the following:
a) Determine and record capacitor-cell voltage rating: _____________
b) Determine and record capacitor-cell kVAR rating: ______________
c) Count capacitor cells on lower rack and upper rack of each phase, and record
results, (below).
[NOTE]
Most capacitor banks are balanced top-to-bottom; some are balanced leftto-right.
X⏀
Y⏀
Z⏀
No. of upper cells
______________
______________
______________
No. of lower cells
______________
______________
______________
Total per phase
______________
______________
______________
d) From Table 01 (below) determine and record capacitor-cell capacitance range.
Min. ________ µf
Max. ________ µf
e) Determine (and record) the phase-capacitance range by multiplying total number
of cells per phase by the min. and max. capacitance-cell values.
(back)
f)
21
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Capacitor Banks, Cells, & Fuses - Inspection & Maintenance Procedures
(46 pgs.)
Total cells per phase
_____________ x
Min. ________ µf
= __________ µf
Total cells per phase
_____________ x
Max. ________ µf
= __________ µf
[top]
3) Measure and record capacitance on each phase.
X⏀ ____________ µf
Y⏀ ____________ µf
Z⏀ ____________ µf
4) Compare individual values obtained in Step C.
a) Value variations should be < half (1/2) of an individual cell’s capacitance.
b) Each phase measurement must fall within the min./max. range established in
Step V, 1, 4, B, v. (phase-capacitance ranges).
i)
If these criteria are met, skip to Step 5: Switcher Diagnostic Sequence.
ii)
If these criteria are NOT met, continue with Step E.
5) Measure and record the capacitance of each rack (which will total six (6)
measurements). The protective grounds by the switcher must be temporarily
removed.
X1⏀ ______________ µf
X2⏀ ______________ µf
Y1⏀ ______________ µf
Y2⏀ ______________ µf
Z1⏀ ______________ µf
Z2⏀ ______________ µf
6) Compare individual values obtained in Step E.
[top]
a) Value variations should be < half (1/2) of an individual cell’s capacitance.
b) Each rack measurement must fall within 50% of the min./max. range established
in Step V, 1, 4, B, v. (phase-capacitance ranges).
i)
If these criteria are NOT met, verify continuity of each capacitor-cell fuse.
•
If a blown fuse is found, measure the cell capacitance.
o
If cell capacitance is within range, replace fuse.
o
If cell capacitance is NOT within range, replace cell AND fuse.
22
© Copyright 2012 | written by Tom Ersin | All Rights Reserved | www.tomersin.com | Capacitor Banks-Cells-Fuses
Capacitor Banks, Cells, & Fuses - Inspection & Maintenance Procedures
ii)
(46 pgs.)
Re-check Step F bulleted requirements. If these criteria still are NOT met
after replacing any blown fuses/bad cells, measure capacitance of each
individual capacitor cell for acceptance.
E) Switcher Diagnosis Sequence
•
Refer to Job procedures:
o
350-015: S&C Circuit Switchers, Vertical & Center Break Models 34.5-kV
through 345-kV
— OR —
o
350-017: Southern States Cap Switcher 72
2) FUSELESS 24-kV & 40-kV
[top]
A) Inspect for, and note, capacitor-cell bulges.
B) Inspect for, and note, YELLOW TARGETS and/or RED TARGETS on capacitor
switcher.
C) Then, follow this troubleshooting sequence:
1) If Step 1 issues (bulged cells) are found, follow Step 4: Capacitor Banks Diagnosis
Sequence (below).
2) If Step 2 issues (targets on switcher) are found, follow Step 5: Switcher Diagnosis
Sequence (below).
3) If Step 1 AND Step 2 issues are found, follow Step 4: Capacitor Banks Diagnosis
Sequence AND Step 5: Switcher Diagnosis Sequence, in-parallel (below).
D) Capacitor Banks Diagnosis Sequence
[top]
1) Verify that “Red Tag Protection” has been applied.
2) Do the following:
a) Determine and record capacitor-cell voltage rating: _____________
b) Determine and record capacitor-cell kVAR rating: ______________
c) From Table 01 (below) determine and record capacitor-cell capacitance range.
23
© Copyright 2012 | written by Tom Ersin | All Rights Reserved | www.tomersin.com | Capacitor Banks-Cells-Fuses
Capacitor Banks, Cells, & Fuses - Inspection & Maintenance Procedures
Min. ________ µf
(46 pgs.)
Max. ________ µf
d) Determine (and record) the phase-capacitance range by dividing total number of
cells per phase by four (4), then multiplying the result by the min. and max.
capacitance-cell values.
Total cells per phase
_____________ x
Min. ________ µf
= __________ µf
Total cells per phase
_____________ x
Max. ________ µf
= __________ µf
[top]
3) Measure and record capacitance on each phase.
X⏀ ____________ µf
Y⏀ ____________ µf
Z⏀ ____________ µf
4) Compare individual values obtained in Step C.
a) Value variations should be < half (1/2) of an individual cell’s capacitance.
b) Each phase measurement must fall within the min./max. range established in
Step V, 2, 4, B, v. (phase-capacitance ranges).
i)
If these criteria are met, skip to Step 5: Switcher Diagnostic Sequence.
ii)
If these criteria are NOT met, continue with Step E.
5) Measure and record the capacitance of “strings” (i.e., groups of capacitor cells inseries). Number of strings could vary depending on capacitor bank size. See Figure
xx to identify strings and measurement points on a typical 24/40-kV - 18 mVAR
fuseless capacitor bank (18 strings, 6 strings per phase).
X1⏀ ______________ µf
X2⏀ ______________ µf
X3⏀ ______________ µf
X4⏀ ______________ µf
X5⏀ ______________ µf
X6⏀ ______________ µf
Y1⏀ ______________ µf
Y2⏀ ______________ µf
Y3⏀ ______________ µf
Y4⏀ ______________ µf
Y5⏀ ______________ µf
Y6⏀ ______________ µf
Z1⏀ ______________ µf
Z2⏀ ______________ µf
Z3⏀ ______________ µf
Z4⏀ ______________ µf
24
© Copyright 2012 | written by Tom Ersin | All Rights Reserved | www.tomersin.com | Capacitor Banks-Cells-Fuses
Capacitor Banks, Cells, & Fuses - Inspection & Maintenance Procedures
Z5⏀ ______________ µf
(46 pgs.)
Z2⏀ ______________ µf
6) Determine the average for values obtained in Step E. All individual string values
should be within ± 0.2 µf of each average.
7) If the average values do not fall within ± 0.2 µf of each average, measure the
capacitance of each cell for acceptance.
E) Switcher Diagnosis Sequence
•
Refer to Job procedures:
o
350-015: S&C Circuit Switchers, Vertical & Center Break Models 34.5-kV
through 345-kV
— OR —
o
350-017: Southern States Cap Switcher 72
Table 01 – Capacitance Value Ranges for Power-Shunt Caps
[top]
UNIT VOLTAGE
RATING (kV)
6.9
6.9
6.9
7.62
12.0
12.0
12.0
12.0
12.0
UNIT POWER
RATING (kVAR)
100
200
500
200
100
200
400
500
550
CAPACITANCE VALUE RANGE
(MICROFARAD)*
MINIMUM
MAXIMUM
5.54
6.49
11.09
12.97
27.72
32.43
9.09
10.64
1.83
2.14
3.67
4.29
7.33
8.58
9.16
10.72
10.08
11.75
* Capacitance value ranges are based on -0% to +15% manufacturing tolerance,
with temperature compensation from -20 degrees Celsius to +40 degrees Celsius.
(back)
(see Figure 17 – Strings and Measurement Points)
25
© Copyright 2012 | written by Tom Ersin | All Rights Reserved | www.tomersin.com | Capacitor Banks-Cells-Fuses
Capacitor Banks, Cells, & Fuses - Inspection & Maintenance Procedures
(46 pgs.)
VI) CAPACITOR BANK BALANCING
(back)
[top]
-) SCOPE
Follow these guidelines for balancing capacitor banks.
1) BALANCING
[top]
If more than one (1) capacitor-cell fuse is found blown on one (1) phase – resulting in an
imbalance – Substation Operator will de-energize capacitor bank and keep it out-of-service
until failed fuses are replaced.
However …
Under certain system conditions, the System Supervisor may require the capacitor bank to
remain in-service, for voltage support, before replacement parts are available. If so,
Substation Operator must balance the capacitor bank to avoid overvoltaging remaining
banks.
A) 13.2-kV BANKS
[top]
•
Wye-ungrounded connection
•
Ratings vary from 3-mVAR to 6-mVAR.
•
200-kVAR capacitor cells
•
Each bank contains three (3) phases.
o
Each phase contains one (1) group.

•
Each group contains capacitor cells connected in-parallel.
BALANCING REQUIRES EACH PHASE GROUP TO CONTAIN SAME NUMBER
OF FUNCTIONING CELLS CONNECTED IN-PARALLEL.
B) 24-kV & 40-kV BANKS
[top]
•
Outdoor rack-type construction
•
Wye-grounded – OR – wye-ungrounded connection
•
Ratings vary from 4.8-mVAR to 30-mMVAR.
26
© Copyright 2012 | written by Tom Ersin | All Rights Reserved | www.tomersin.com | Capacitor Banks-Cells-Fuses
Capacitor Banks, Cells, & Fuses - Inspection & Maintenance Procedures
•
o
4.8-mVAR banks use 100-kVAR capacitor cells.
o
30-mVAR banks use 200-kVAR capacitor cells.
Each bank contains three (3) phases.
o
Each phase contains two (2) racks (in an upper/lower OR right/left configuration)
connected in-series.

•
(46 pgs.)
Each rack contains capacitor cells connected in-parallel.
BALANCING REQUIRES EACH RACK – OF ALL THREE (3) RACK
CONFIGURATIONS (PAIRS) – TO HAVE SAME NUMBER OF FUNCTIONING
CAPACITOR CELLS CONNECTED IN-PARALLEL.
[NOTE]
A few small-size capacitor banks contain only one (1) rack per phase.
•
Each bank contains three (3) phases.
o
Each phase contains one (1) rack.

Each rack contains two (2) sides connected in-series.
o
•
Each side contains capacitor cells connected in-parallel.
BALANCING REQUIRES EACH SIDE – OF ALL THREE (3) RACKS – TO HAVE
SAME NUMBER OF FUNCTIONING CAPACITOR CELLS CONNECTED INPARALLEL.
1) WYE-UNGROUNDED (see Figures 01 & 02)
[top]
a) Upper Rack In-Series with Lower Rack (see Figure 01)
•
To balance 24-kV or 40-kV ungrounded capacitor banks, each rack (upper
and lower) of all three (3) phases must contain same number of capacitor
cells, connected in-parallel.
b) Left-Side Rack In-Series with Right-Side Rack (see Figure 02)
•
To balance 24-kV or 40-kV ungrounded capacitor banks, each rack (left-side
and right-side) of all three (3) phases must contain same number of capacitor
cells, connected in-parallel.
c) One Side of Small Bank In-Series with Other Side of Small Bank
27
© Copyright 2012 | written by Tom Ersin | All Rights Reserved | www.tomersin.com | Capacitor Banks-Cells-Fuses
Capacitor Banks, Cells, & Fuses - Inspection & Maintenance Procedures
•
(46 pgs.)
To balance 24-kV or 40-kV ungrounded capacitor banks, each small bank
(both sides or groups) of all three (3) phases must contain same number of
capacitor cells, connected in-parallel.
2) WYE-GROUNDED (see Figures 03 & 04)
[top]
Since each phase of 24-kV or 40-kV grounded capacitor banks can be independently
balanced, the number of connected capacitor cells per phase can be unequal without
causing an overvoltage condition.
a) Upper Rack In-Series with Lower Rack (see Figure 03)
•
To balance 24-kV or 40-kV grounded capacitor banks within each phase, the
number of capacitor cells on lower rack must equal number of capacitor cells
on upper rack.
b) Left-Side Rack In-Series With Right-Side Rack (see Figure 04)
•
To balance 24-kV or 40-kV grounded capacitor banks within each phase, the
number of capacitor cells on left-side rack must equal number of capacitor
cells on right-side rack.
2) GENERAL
[top]
A) When balancing a capacitor bank, Substation Operator will completely remove
disconnected (blown) fuse element – or secure it – to prevent its contact (aka “leader
whipping”) with capacitor-bank frame, another fuse, or another capacitor cell.
B) On capacitor banks containing current-limiting fuses, Substation Operator will conduct a
continuity check of ALL limiters following a blown-fuse replacement or a capacitor-bank
balancing operation. Defective current limiters cause voltage imbalances on in-service
capacitor cells.
C) Fuseless capacitor banks cannot be balanced.
VII) CAPACITOR (aka “SHUNT CAPACITOR”) THEORY &
OPERATION
[top]
1) PURPOSE
Capacitors (aka “shunt capacitors”) are installed throughout the DECO electrical system.
When installed near an inductive load, capacitors improve voltage regulation and allow
additional equipment capacity. Therefore, system-load capacity is increased.
Here’s how:
28
© Copyright 2012 | written by Tom Ersin | All Rights Reserved | www.tomersin.com | Capacitor Banks-Cells-Fuses
Capacitor Banks, Cells, & Fuses - Inspection & Maintenance Procedures
(46 pgs.)
A) Induction motors, transformers, and other inductive equipment draw a line current
greater than the actual power they consume. This happens because the magnetizing
current in the circuit (produced as the magnetic fields build up and collapse within each
cycle) reaches its maximum value one quarter of a cycle LATER than the voltage wave
does (LAGGING the impressed voltage by 90°).
B) Capacitors draw a current that reaches their maximum value one quarter of a cycle
SOONER than the voltage wave does (LEADING the impressed voltage by 90°).
C) Therefore, capacitor current is 180° out-of-phase (exactly opposite) with the
magnetizing current supplied by inductive equipment (motors, transformers, etc.). So
when a load comprising inductive AND capacitive equipment is connected to a line, the
magnetizing current (between capacitor and generator) is reduced by the capacitorcurrent level.
D) (See Figure 10) As shown, if E is the direction of the voltage, Ip is the current supplying
the useful power, and Im is the magnetizing current, then Il is the line current (produced
by “graphic addition”). As a result, Il is greater than Ip by the current amount needed
to supply useful power.
E) Consider a capacitor drawing current Ic – and an equal but opposite current Im. If these
two were now connected in-parallel, Ic and Im would balance out, and the total line
current would coincide with Ip in magnitude and direction.
1) The power current Ip, multiplied by voltage, equals “true power” (kW).
2) The line current Il, multiplied by voltage, equals “apparent power” (kVA).
3) The ratio of true power to apparent power (kW : kVA) is the “power factor” of the
circuit.
Capacitors are connected to the system during heavy-load periods. This produces the
following effects:
A) Raises power factor of load and system as a whole.
•
Amount of power-factor improvement depends on amount of reactive load and
amount of connected capacitance.
B) Causes voltage to rise at the load.
•
Amount of voltage increase depends on amount of reactive drop and amount of
connected capacitance.
To obtain optimum voltage regulation, capacitors are connected to, AND
disconnected from, the DTE Energy electrical system by automatic switchgear.
29
© Copyright 2012 | written by Tom Ersin | All Rights Reserved | www.tomersin.com | Capacitor Banks-Cells-Fuses
Capacitor Banks, Cells, & Fuses - Inspection & Maintenance Procedures
•
(46 pgs.)
This switchgear can be controlled automatically (by time clocks or VAR controllers), OR
can be controlled manually by Substation Operator.
Because amount of magnetizing current (identified as “Im” in Figure 10) is reduced,
more load-carrying capacity becomes available.
•
Indeed, if Ic should exceed Im, load would contain a leading power factor, causing
voltage to rise.
•
This can cause transformers, lines, etc., to have a greater load AFTER capacitor is
online than before it was connected.
On the DTE Energy system, capacitor use is frequently manipulated by System
Supervisor to maintain 24-kV and 40-kV buss voltage while incoming transmission
lines are out-of-service during light-load periods.
2) CONSTRUCTION & CONNECTIONS
[top]
A) Capacitor Cells
1) Each capacitor-bank cell contains two (2) bushings (13.2-kV metal-enclosed cap
banks and fuseless) or one (1) bushing (24-kV and 40-kV fused cap banks). In all
cases bushings are insulated from their case and connected to special thin-foil paper
layers.
•
The paper layers are infused with refined mineral oil – OR – synthetic chlorinated
biphenyl.
o
Neither is flammable or explosive.
2) With fused capacitor banks, each capacitor cell’s source side is fused with an
indicating-type high-voltage power fuse.
B) Capacitor Bank Installations
[top]
•
On Westinghouse, GE, and Cooper (McGraw-Edison) capacitor-bank installations,
individual capacitor cells are supported by an insulated rack. (see Figure 09)
o
This rack is energized from the parallel series combination’s midpoint.
C) Capacitor Discharge
[top]
3) Capacitors retain a dangerous charge even after their energy source has been
removed.
30
© Copyright 2012 | written by Tom Ersin | All Rights Reserved | www.tomersin.com | Capacitor Banks-Cells-Fuses
Capacitor Banks, Cells, & Fuses - Inspection & Maintenance Procedures
•
(46 pgs.)
Therefore, it is mandatory that capacitor-bank installations be discharged
before any work is performed on them.
4) As shown in Figure 08, upon removal of energy source, entire capacitor bank will
discharge down to a 50-volt level within five (5) minutes.
5) As a further safeguard, all three (3) capacitor-bank phases – and the insulated rack –
are grounded by ground switches – OR – a set of removable grounding leads, which
Substation Operator must install before any capacitor equipment work is performed.
3) OPERATING INFORMATION
[top]
A) A capacitor may retain above-normal operating voltages after disconnection from the
line.
•
These voltages are dependent upon the voltage-wave resting point when circuit
breaker was opened.
B) Therefore, whenever a capacitor is de-energized, wait at least five (5) minutes before
re-energizing it.
•
Otherwise, excessive capacitor voltage may damage equipment connected to the
bus.
C) Whenever a capacitor is connected to a bus, the current surges two (2) to three (3)
times normal during first 1/4 to 1/2 cycle.
[top]
31
© Copyright 2012 | written by Tom Ersin | All Rights Reserved | www.tomersin.com | Capacitor Banks-Cells-Fuses
Capacitor Banks, Cells, & Fuses - Inspection & Maintenance Procedures
(46 pgs.)
Figure 01 — Wye-Ungrounded Capacitor Bank – Upper Rack In-Series with Lower Rack
(back)
[top]
32
© Copyright 2012 | written by Tom Ersin | All Rights Reserved | www.tomersin.com | Capacitor Banks-Cells-Fuses
Capacitor Banks, Cells, & Fuses - Inspection & Maintenance Procedures
(46 pgs.)
Figure 02 — Wye-Ungrounded Capacitor Bank – Left-Side Rack In-Series with Right-Side Rack
(back)
[top]
33
© Copyright 2012 | written by Tom Ersin | All Rights Reserved | www.tomersin.com | Capacitor Banks-Cells-Fuses
Capacitor Banks, Cells, & Fuses - Inspection & Maintenance Procedures
(46 pgs.)
Figure 03 — Wye-Grounded Capacitor Bank – Upper Rack In-Series with Lower Rack
(back)
[top]
34
© Copyright 2012 | written by Tom Ersin | All Rights Reserved | www.tomersin.com | Capacitor Banks-Cells-Fuses
Capacitor Banks, Cells, & Fuses - Inspection & Maintenance Procedures
(46 pgs.)
Figure 04 — Wye-Grounded Capacitor Bank – Left-Side Rack In-Series with Right-Side Rack
(back)
[top]
35
© Copyright 2012 | written by Tom Ersin | All Rights Reserved | www.tomersin.com | Capacitor Banks-Cells-Fuses
Capacitor Banks, Cells, & Fuses - Inspection & Maintenance Procedures
(46 pgs.)
Figure 05 — Voltage-Sensing Potential Device
(back)
[top]
36
© Copyright 2012 | written by Tom Ersin | All Rights Reserved | www.tomersin.com | Capacitor Banks-Cells-Fuses
Capacitor Banks, Cells, & Fuses - Inspection & Maintenance Procedures
(46 pgs.)
Figure 06 — Lockout Relay (LOR)
(back)
[top]
37
© Copyright 2012 | written by Tom Ersin | All Rights Reserved | www.tomersin.com | Capacitor Banks-Cells-Fuses
Capacitor Banks, Cells, & Fuses - Inspection & Maintenance Procedures
(46 pgs.)
Figure 07 — Fuses, Construction, & Connections
(back)
[top]
38
© Copyright 2012 | written by Tom Ersin | All Rights Reserved | www.tomersin.com | Capacitor Banks-Cells-Fuses
Capacitor Banks, Cells, & Fuses - Inspection & Maintenance Procedures
(46 pgs.)
Figure 08 — Capacitor Bank Group & Fuses
(back)
[top]
Figure 09 — Capacitor Bank Installations
(back)
[top]
39
© Copyright 2012 | written by Tom Ersin | All Rights Reserved | www.tomersin.com | Capacitor Banks-Cells-Fuses
Capacitor Banks, Cells, & Fuses - Inspection & Maintenance Procedures
(46 pgs.)
Figure 10 — Current Flow
(back)
[top]
Figure 11 — Fluke Multi-Meter
(back)
[top]
40
© Copyright 2012 | written by Tom Ersin | All Rights Reserved | www.tomersin.com | Capacitor Banks-Cells-Fuses
Capacitor Banks, Cells, & Fuses - Inspection & Maintenance Procedures
(46 pgs.)
Figure 12 — Fluke Multi-Meter
(back)
[top]
41
© Copyright 2012 | written by Tom Ersin | All Rights Reserved | www.tomersin.com | Capacitor Banks-Cells-Fuses
Capacitor Banks, Cells, & Fuses - Inspection & Maintenance Procedures
(46 pgs.)
Figure 13 — Fuse Element Components
(back)
[top]
42
© Copyright 2012 | written by Tom Ersin | All Rights Reserved | www.tomersin.com | Capacitor Banks-Cells-Fuses
Capacitor Banks, Cells, & Fuses - Inspection & Maintenance Procedures
(46 pgs.)
Figure 14 — Fuse Element – Horizontal Bushing Assembly
(back)
[top]
43
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Capacitor Banks, Cells, & Fuses - Inspection & Maintenance Procedures
(46 pgs.)
Figure 15 — Fuse Element – Vertical Bushing Assembly
(back)
[top]
44
© Copyright 2012 | written by Tom Ersin | All Rights Reserved | www.tomersin.com | Capacitor Banks-Cells-Fuses
Capacitor Banks, Cells, & Fuses - Inspection & Maintenance Procedures
(46 pgs.)
Figure 16 — Springs – Old and New Style
(back)
[top]
45
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Capacitor Banks, Cells, & Fuses - Inspection & Maintenance Procedures
(46 pgs.)
Figure 17 — Strings & Measurement Points
(back)
[top]